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\usepackage{tikz}
\usetikzlibrary{snakes,arrows,shapes}
\usepackage{amsmath}
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\usepackage[active,tightpage]{preview}
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\usetikzlibrary{automata}%

\begin{document}
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\enlargethispage{100cm}
% Start of code
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% End of code

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\end{document}
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